Sherlock short attached on Amazon?

I just watched this on amazon prime.

When the boat captain came and the two survivors headed to the boat, I assumed the movie was over and got up to do dishes.

Then I realized it was still playing from the other room. There was a Sherlock HOlmes short attached at the end that seemed to have nothing to do with the movie. I missed most of it, but once I realized something was still playing I caught the end, which seemed to be a little old lady tried to poison someone with divinity fudge, and sherlock (or maybe it was lestrade) tried to feed some to the lady's birds before he would eat it himself, to which she flipped out, and they realized she had tried to poison them. At the very end she said she was sorry she tried to poison them

It was just weird. Was it something tucked in from the old days when it might have played between a double feature? There didn't seem to be any credits onit. I just found it terribly confusing.

...Madness takes its toll...